This disclosure relates generally to bearing systems and methods. More particularly, this disclosure relates to non-contact, fluid bearing systems and methods.
Fluid bearing systems may be used in vehicular or transport systems, including high-speed transport systems for reducing friction between the moving vehicle and an adjacent surface over which the vehicle travels. For example, the Hyperloop system is a recent concept that has the potential to become a new, “fifth mode” of transportation, after the classic four: automobiles, trains, ships, and planes. The Hyperloop system may rely on the high-speed, near transonic movement of a vehicle or pod, resembling a train, in a tube that carries human passengers and/or cargo. Space requirements, cost arguments, and other practical considerations may limit the types of propulsion and the amount of thrust available for pod motion inside the tube. Therefore, for the Hyperloop system to come to fruition, all sources of drag resisting pod motion may be minimized. Two major sources of drag include aerodynamic drag, and rolling friction due to wheel contact. Aerodynamic drag may be addressed by evacuating the Hyperloop tube to low pressures, while rolling friction may be addressed by levitating the pod and thus eliminating contact friction altogether.
Levitation of a vehicle may be achieved by relying on electromagnetic means, i.e., by utilizing some type of inductive force generation, or arrangements of rotating magnets, as for example in the Halbach array. However, such devices require electrical power that is carried onboard (e.g. batteries), or is supplied to the moving pod from the ground. A second levitation method may employ gas (e.g., air, etc.) bearings that rely on the presence of compressed gas onboard the pod. One of the more significant problems of air bearing technology is the very small levitation height that can be generated for realistic gas pressure and flowrate conditions. In some applications, commercially available gas bearings may produce a levitation height on the order of few tens of micrometers (i.e., few thousands of an inch). This relatively minimal levitation height may be insufficient to support travel over rough or uneven terrain at high speeds.